improved eslint config, refactoring and documentation

Author: KyroHub

.github/workflows/ci.yml

@@ -37,6 +37,9 @@ jobs:
       - name: Check formatting
         run: npm run format:check
 
+      - name: Check dead code
+        run: npm run knip
+
       - name: Run lint
         run: npm run lint
 

.gitignore

@@ -45,3 +45,11 @@ supabase/.temp/
 # typescript
 *.tsbuildinfo
 next-env.d.ts
+
+# temp/scratch scripts and outputs
+/scratch/
+knip.txt
+knip.out.json
+lint.json
+fix_*.mjs
+fix_*.js

CONTRIBUTING.md

@@ -103,6 +103,7 @@ Before opening a PR, run:
 
 ```bash
 npm run format:check
+npm run knip
 npm run lint
 npm run test
 npm run build

eslint.config.mjs

@@ -1,18 +1,139 @@
 import { defineConfig, globalIgnores } from "eslint/config";
 import nextVitals from "eslint-config-next/core-web-vitals";
 import nextTs from "eslint-config-next/typescript";
+import importPlugin from "eslint-plugin-import";
 
 const eslintConfig = defineConfig([
   ...nextVitals,
   ...nextTs,
-  // Override default ignores of eslint-config-next.
+  {
+    linterOptions: {
+      reportUnusedDisableDirectives: "error",
+    },
+  },
+  {
+    files: ["src/**/*.{ts,tsx,mts}", "supabase/functions/**/*.ts"],
+    plugins: {
+      import: importPlugin,
+    },
+    rules: {
+      "@typescript-eslint/consistent-type-imports": [
+        "error",
+        {
+          prefer: "type-imports",
+          fixStyle: "separate-type-imports",
+          disallowTypeAnnotations: false,
+        },
+      ],
+      "@typescript-eslint/no-unused-vars": [
+        "error",
+        {
+          argsIgnorePattern: "^_",
+          varsIgnorePattern: "^_",
+          caughtErrorsIgnorePattern: "^_",
+        },
+      ],
+      curly: ["error", "all"],
+      eqeqeq: ["error", "always"],
+      "import/first": "error",
+      "import/no-duplicates": "error",
+      "no-console": ["error", { allow: ["warn", "error"] }],
+      "no-else-return": "error",
+      "no-nested-ternary": "error",
+      "no-unneeded-ternary": "error",
+      "prefer-template": "error",
+    },
+  },
+  {
+    files: ["src/**/*.{ts,tsx,mts}"],
+    ignores: ["src/**/*.test.ts", "src/content/**"],
+    rules: {
+      "no-restricted-imports": [
+        "error",
+        {
+          patterns: [
+            {
+              group: ["../../../*", "../../../../*", "../../../../../*"],
+              message:
+                "Prefer @/ aliases or feature-local imports over deep parent-relative paths.",
+            },
+          ],
+        },
+      ],
+    },
+  },
+  {
+    files: ["src/**/*.{ts,tsx,mts}", "supabase/functions/**/*.ts"],
+    rules: {
+      "import/order": [
+        "error",
+        {
+          groups: [
+            "builtin",
+            "external",
+            "internal",
+            ["parent", "sibling", "index"],
+            "type",
+          ],
+          "newlines-between": "always",
+          alphabetize: {
+            order: "asc",
+            caseInsensitive: true,
+          },
+          pathGroups: [
+            {
+              pattern: "@/**",
+              group: "internal",
+              position: "before",
+            },
+          ],
+          pathGroupsExcludedImportTypes: ["builtin"],
+        },
+      ],
+    },
+  },
+  {
+    files: ["src/actions/**/*.{ts,tsx,mts}"],
+    ignores: ["src/**/*.test.ts", "src/**/*.test-helpers.ts"],
+    rules: {
+      "@typescript-eslint/explicit-module-boundary-types": [
+        "warn",
+        {
+          allowArgumentsExplicitlyTypedAsAny: true,
+        },
+      ],
+    },
+  },
+  {
+    files: [
+      "src/actions/**/*.{ts,tsx,mts}",
+      "src/lib/**/*.{ts,tsx,mts}",
+      "supabase/functions/**/*.ts",
+    ],
+    ignores: ["src/**/*.test.ts", "src/**/*.test-helpers.ts"],
+    rules: {
+      complexity: ["warn", 10],
+      "max-depth": ["warn", 3],
+      "max-lines-per-function": [
+        "warn",
+        {
+          max: 80,
+          skipBlankLines: true,
+          skipComments: true,
+        },
+      ],
+      "max-nested-callbacks": ["warn", 2],
+    },
+  },
+  /**
+   * Preserve Next's default generated-file ignores and extend them with the
+   * artifacts created by test and coverage tooling.
+   */
   globalIgnores([
-    // Default ignores of eslint-config-next:
     ".next/**",
     "out/**",
     "build/**",
     "next-env.d.ts",
-    // Generated test artifacts:
     "playwright-report/**",
     "test-results/**",
     "coverage/**",

knip.json

@@ -0,0 +1,14 @@
+{
+  "$schema": "https://unpkg.com/knip@5/schema-json",
+  "entry": [
+    "src/app/**/{page,layout,loading,not-found,error,route}.ts?(x)",
+    "supabase/functions/**/index.ts",
+    "scripts/**/*.mts"
+  ],
+  "project": [
+    "src/**/*.{ts,tsx}",
+    "supabase/functions/**/*.ts",
+    "scripts/**/*.mts"
+  ],
+  "ignoreDependencies": ["tailwindcss"]
+}